Ariew and Lewontin, "Fitness Confusions"

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Thank you for weighing in, however in our chapter we introduced an alternative viewpoint for fitness.

The Springer-Nature chapter we co-authored suggested an alternative and modified view of fitness along the lines of Bialek. We specifically mentioned but did not elaborate as it was not the point of the paper:

Lewontin lamented that the population genetic definition of fitness was becoming
nothing more than a restatement of reproductive schedules, instead of describing
fitness in terms of an organism’s capabilities in relation to its environment. It can
be asserted that on a pragmatic level, fitness is most simply understood as total
biological functionality in a given context.

Figure or Merit was suggested by David Snoke.

In discussions with others, we have bumped around the idea of metrics of of performance and capabilities along engineering lines.

We did say in our reference chapter:

There are other aspects of fitness theory that are even more fundamental than
those just outlined. These go to the core question involving the actual meaning
of “fitness.” Years after Lewontin’s research confirmed Moran’s work, Lewontin
said, “it is not entirely clear what fitness is.” Because population geneticists defined
fitness solely in terms of reproductive success, Lewontin said, “Darwin’s sense
of fit has been completely bypassed.” Lewontin wrote in a 2003 essay describing
unresolved complications with the evolutionary process (Lewontin 2003):
The problem is that it is not entirely clear what fitness is. Darwin took the metaphorical
sense of fitness literally. The natural properties of different types resulted in their differential
“fit” into the environment in which they lived. The better the fit to the environment the more
likely they were to survive and the greater their rate of reproduction. This differential rate
of reproduction would then result in a change of abundance of the different types.
In modern evolutionary theory, however, “fitness” is no longer a characterization of the
relation of the organism to the environment that leads to reproductive consequences, but is
meant to be a quantitative expression of the differential reproductive schedules themselves.
Darwin’s sense of fit has been completely bypassed …
Darwin’s notion was the common-sense notion whereby an organism is fit for an
environment because it has the organs and functionalities that enable it to live in its
habitat. In engineering terms, a spaceship is fit to operate in space, a submarine is fit
to operate undersea, a car operates on the ground, an airplane in the air. A common
sense understanding of fitness is best understood in a pragmatic sense, i.e., total
functionality in a specific context. In this pragmatic sense, fitness can be discerned
apart from the complexities of reproductive success through deep time. With this in
mind, there is a very strong case for a return to the common-sense notion of fitness
as simply a measure of total functionality

This supercedes the antiquated notion of fitness solely in terms of a single unitary scalar that represents reproductive efficiency in only one enviornment, and thus the genetic entorpy argument is even stronger than the 2005 version that used the antiquated single unintary scalar tied to reproductive efficiency.

When in Lenski’s LTEE mutator genomes that decayed its genomes despite sustained fitness gains, it lost versatility. Versatility refers to other biological contexts.

When we wrote our chapter in 2020, none of us was aware of the titles “genomes decay despite sustained fitness” gains nor or “gene loss by natural selection”, however we were aware of “genome reduction as the dominant mode of evolution”.

I expect discussion of and publication of a reviesed viewpoint of what it means to be fit, will be more along engineering lines rather than solely in terms of reproductive efficiency.

Survival of an individual is more than the individuals ability to make offspring. A submarine does not make offspring, but it is clearly “fit” to operate in an underwater context in terms of propulsion and navigation. An functioning aircraft is fit to fly, a functioning car is fit to drive, etc.

It appears Darwin tried to correlate reproductive efficiency to the evolution of “organs of extreme complication and perfection”. It appears reproductive efficiency is actually anti-correlated to complexity, hence the most reproductively efficient creatures are the simplest ones, and the most complex are the least reproductively efficient pound for pound.

Much of Genetic Entropy theory from Dr. Sanford 2005 paper was based on the antiquated view of fitness common in evolutionary and population genetic literature. I was the co-author adamant about citing Lewontin and Andreas Wagner. As our chapter got circulated, we were referred to even more literature and experiments.

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Hey, Sal!

Your latest post doesn’t properly reflect your character and ability. I suggest you rewrite it like this:

Thank you for weighing in, however in our chapter we invented an alternative viewpoint for fitness.

The Springer-Nature chapter we co-authored suggested an alternative and modified view of fitness along the lines of some-one who I’m going to say was Bialek, even though I know it may have been one of his co-authors. We specifically mentioned but did not elaborate in case we gave away enough to allow you to check whether we were misrepresenting him:

Lewontin lamented - well, we say lamented, but he may have been pleased, indifferent, bored, astonished or even ecstatic - that the population genetic definition of fitness was becoming
nothing more than a restatement of reproductive schedules, instead of describing
fitness in terms of an organism’s capabilities in relation to its environment. But you can’t trust us to represent him honestly, so don’t bother reading the rest.

Figure or Merit was suggested by David Snoke. Or maybe Behe. For all you know it was Behe describing Games Workshop’s output as "Minifigures of merit* and we chopped off the Mini.

In discussions with others who may or may not exist, we have bummed around making fatuous claims about analysing fish as if they were speedboats.

We quoted Lewontin (our favorite!) in our reference chapter, but you know we can’t be trusted, so skip this bit:

Why are you reading this? We told you to skip it!

We want to pretend the notion of fitness solely in terms of a single unitary scalar is antiquated because we want you to think it’s been replaced by our exciting! new! bafflegab! even though it hasn’t. Incidentally, we want to pretend that ‘fit’ and ‘fitness’ are the same word so that we can cite Lenowtin writing ‘fit’ as an excuse to reject ‘fitness’. This would make our genetic epnorty argument even stronger than the 2005 version that is as powerful as tissue-paper.

When in Lenski’s LTEE mutator genomes that decayed its genomes despite sustained fitness gains, it lost versatility. Versatility refers to other biological contexts, and we’re pretending that Lenski (except it wasn’t Lenski) was talking about them too, even though we know he wasn’t.

When we wrote our chapter in 2020, none of us was aware of the extracts from titles “genomes decay despite sustained fitness” gains nor or “gene loss by natural selection”, but now we are aware of them we’re going to misuse them to the point you won’t trust anything we say.

I expect discussion of and publication of a reviesed viewpoint of what it means to be fit, will be more along engineering lines rather than solely in terms of reproductive efficiency, but I know our ‘work’ is a pile of manure and that it’ll only be discussed by other manure-pilers while mainstream scientists ignore it completely. But what the hell, we’ll claim to be influential anyway.

Survival of an individual is more than the individuals ability to make offspring. A submarine does not make offspring, so is completely irrelevant to biological evolution, but I’m mentioning it in the hope that you are an idiot.

It appears Darwin wrote “organs of extreme complication and perfection”, so I’m going to quote-mine that phrase and not link to anything Darwin wrote, in the hope that you don’t check what he really said in case you find out it was actually a chapter title and nothing to do with what I claimed.

Much of Genetic Entropy theory from Dr. Sanford 2005 paper (which wasn’t just by him, but who cares about citing people of lesser renown?) was also based on quote-mines and misrepresentations, as well as appallingly bad maths that would have disgraced a high-schooler. I was the co-author who wanted to quote-mine Lewontin and Andrew Waggoner. As our chapter got circulated we were referred to even more material about which we could lie our socks off.

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83

Exactly.

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84

No, it doesn’t. Say you’ve got antibiotic resistance encoded by a gene that works as an enzyme that breaks down an antibiotic you never encounter. It’s a waste, literally detrimental to your long term ability to survive and reproduce. By your silly metric it would be a loss of “fitness” to get rid of this gene.

No because all you’ve done is invented a metric that isn’t something evolution has to always produce more of. It just isn’t a requirement that the process of evolution must always and only ever produce increases in functional versatility that never decays or goes away again, in order for the evolutionary history of the planet as currently inferred to have actually occurred.

The extant concept of fitness doesn’t need to be replaced by this weird measure of total functional “versatility” for us to understand how evolution happens and how fitness is a component of it, and you don’t show that evolution is false or doesn’t happen because it doesn’t produce ever more “versatility” always and under all circumstances.

There isn’t a transition in the known evolutionary history of life that did not involve some sort of compromise or trade-off, where gains in one thing didn’t come at the cost of some other thing. When the ancestors of whales evolved to swim in the oceans, they lost their terrestrial versatility. Same goes for the transition from fish to tetrapods.

Even in our own species recent history we clearly traded increases in some capacities for reductions or losses in others. Absolute physical strength, how well we can climb in trees, sense of smell, hearing, etc. were traded for increase intelligence, communication, bipedalism and so on.

Ironically there are basic engineering principles that explain why all possible metrics of absolute functional capacity can’t simultaneously maximize in the same entity. The strongest material isn’t the lightest, birds have notoriously brittle bones, the largest animals live in water. A race car is light and fragile, a tank is slow and heavy. You can make a fast tank but it won’t be able to turn at high speed because of momentum.

You think you have thought about this, but you haven’t. You need to think more.

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85

Darwin literally has a chapter on vestigial traits, use and disuse or organs, and things that are eventually rendered nonfunctional and lost because it is of no value to survival and reproduction. He begins by giving the example of loss of flight and the deterioration of wings in flightless birds. You once again prove you haven’t even read the book. Are you that afraid of it?

By inventing a concept of absolute functional versatility, and then pointing out real evolution doesn’t produce ever more of it, you’re only showing the concept doesn’t work and that in fact Darwin was right about what evolution is and how adaptation occurs.

LOL. Nice own goal!

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86

It may be a waste, but it’s unlikely, except perhaps in bacteria, to be enough a waste to affect fitness or to be visible to selection. And that’s why we have so much junk DNA. It’s unlikely to be either a loss or gain of fitness to get rid of any of it.

OK, fitness depends on environment. But shouldn’t it? Shouldn’t “merit” also depend on environment? How does Sal’s measure account for that? Is it operational at all? Can we even estimate the “merit” of any organism or genotype?

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87

If the gene is not expressed the cost of that extra DNA itself is effectively invisible to selection. But I’d bet it’s expression level if high enough can alter that cost so either the loss or at least inactivation of the gene would be favored. Many of the gene losses Sal has referred to have happened in multicellular eukaryotes, where they just became pseudogenized in various ways (ok many of those probably just lost maintenance by puryfying selection, rather than being positively selected for inactivation). Those would count as gene loss even if the entire locus is still present.

Exactly my point. If Sal insists this versatility/merit/functionality/gene content-measure must only ever increase, then it isn’t evolution and such a process can’t explain the history of life on Earth, with it’s many periods of stasis or simplification for innumerable clades and lineages.

By comparing his measure to the fossil record, and to what happens in experiments, we see that this thing he insists that evolution must always do, rarely happens, so his metric is proven false empirically, and instead the extant theory of evolution much better fits the pattern observed in experiments and in the fossil record.

According to Sal’s buddies concept, fish should have evolved wings, big brains, tree climbing, spider nets, burrowing paws, fur, feathers, photosynthesis, leaves and roots, bark, legs and arms, eyes all over but also blindness in case it needs to live in a dark cave or underground, both lungs and gills, tentacles, a segmented, scaled, muscled body covered in chameleonic bioluminescent skin. All at the same time. And when this doesn’t happen and hasn’t happened anywhere in the fossil record, then … we need a new concept of fitness because evolution is false?

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88

Possibly, but the expression level would have to be extremely high for there to be a cost significant enough to affect fitness. I doubt the great majority of genes would fit that category, and almost certainly not a useless one.

Let’s remember that Sal doesn’t believe in evolution, and possibly not in the great age of the fossil record. (He has at times professed support for the “old earth, young life” position.) And remember that he thinks that such evolution as he allows just results in genetic entropy. He picks a measure of “merit” that can be used to suport genetic entropy in principle. Doesn’t matter whether it’s operational, because data are irrelevant, even deceptive.

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Ah, but don’t you see? That only proves that evolution (as Sal and his buddies understand it) never happens and therefore the theory is false.

Praise Jesus.

90

Please, let’s not have criticism of Sal’s science spill over to criticism of his religion.

91

Science?

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92

Whatever it is, it’s fair game.

93

I agree with Lewotin. There. That was easy. A simple YES.

How about you? A simple YES or NO will suffice.

94

I am not criticizing his religion. Rather, I am criticizing his failure to distinguish between his religion and science. Sorry if that was not clear.

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95

Presumably you’d also prefer that criticism of his dishonesty not spill over to criticism of his religion.

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96

While I am not comfortable with satirizing faith, clarity demands that it be recognized that Sanford and Sal are not offering a solution to any scientific problem here. The classical notion of fitness works just fine. This attempt at redefining the vernacular is a thin wrapper over Milton’s Paradise Lost.

Reproductive success integrates the contribution of all the biological functionalities in a given environment that Sal is blathering about. That is only, how do I say…common sense.

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You forgot to answer the second question, without which any answer to the first is meaningless.

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98

s/forgot/neglected/p

But that’s not surprising. a ‘yes’ would lead to unanswerable (by Sal) questions about Lewontin’s meaning; a ‘no’ would lead to unanswerable (By Sal) questions about integrity.

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99

We all do.

Evolution isn’t required to be the opposite of how you have defined Genetic Entropy, where you imagine in GE it only ever produces the loss of something (total number of functions or whatever.)

In order for evolution to be true it doesn’t have to be the case that it must only produce increases in number of genes/functions/complexity under all circumstances. Heck, it doesn’t even have to produce an indefinite and continuous net gain in reproductive fitness, as that too can fluctuate up and down over time.

And yet reproductive fitness is a perfectly comprehensible and useable concept that can remain specific to a circumstance (environmental and genetic), so A can outcompete B under that circumstance and thus A be fitter than B.

We’ve been over this already.

100

I think I understand. So YES to both. But if I don’t understand according to you, I’m willing to change my mind and say NO. But it doesn’t matter because I’d say Lewontin is a better authority on these matters than you, so I’ll agree with him even if you say “NO”. If you say, “YES” then you and I are in agreement on question 1. And finally we agree on something.

Now you’re turn. I’ll make it easy for you. Why don’t you answer whether you agree with Lewontin. Do you partially agree, completely agree, completely disagree. It’s not that hard a question, John.

His paper is after all the topic of the discussion, and it would be helpful if you gave your opinion on the veracity of his claims.